The primary purpose of this project is to describe and evalute the distribution of cancer occurrence in the United States in terms of age, sex, race, place and time in order to identify subgroups of the population that offer possibilities for mortality reduction through intervention. Cancer incidence and mortality rates are analyzed using biostatistical techniques such as log-linear models or model derived from the multistage theory of carcinogenesis. Incidence data from the SEER Program and mortality data from the National Center for Health Statistics together with other data sources are often the focus of such analyses. Analysis of incidence rates for pleural and peritoneal mesothelioma in the United States revealed an increase over time for pleural mesothelioma among while males but not for females nor for periotoneal mesothelioma among either sex. Incidence rates were highest in seaboard areas where shipyards have been located. Mortality rates for pleural cancer were elevated in several areas of the country that have had asbestos manufacturing plants or shipyards. Choriocarcinoma incidence rates were recently evaluated based on the total female population and also according to the number of pregnancies in the population, a more appropriate denominator since nearly all trophoblastic tumors are related to conception. After adjustment for age and birth effects, whites demonstrated the lowest rates, with blacks and those of other races being at elevated risk. A recent study of the geographic patterns in nasopharyngeal cancer mortality rates in the United States utilized a system of economic subregions to advantage. The 3,056 counties in the country were grouped in 199 subregions with similar socioeconomic characteristics. For white males, clusters of high death rates along the Gulf Coast and southeast Atlantic Coast were clearly evident at the subregion level but not at the county level.